我有几个输入要使用//
// AxesDrawer.swift
// Calculator
//
// Created by CS193p Instructor.
// Copyright © 2015-17 Stanford University.
// All rights reserved.
//
import UIKit
struct AxesDrawer
{
var color: UIColor
var contentScaleFactor: CGFloat // set this from UIView's contentScaleFactor to position axes with maximum accuracy
var minimumPointsPerHashmark: CGFloat = 40 // public even though init doesn't accommodate setting it (it's rare to want to change it)
init(color: UIColor = UIColor.blue, contentScaleFactor: CGFloat = 1) {
self.color = color
self.contentScaleFactor = contentScaleFactor
}
// this method is the heart of the AxesDrawer
// it draws in the current graphic context's coordinate system
// therefore origin and bounds must be in the current graphics context's coordinate system
// pointsPerUnit is essentially the "scale" of the axes
// e.g. if you wanted there to be 100 points along an axis between -1 and 1,
// you'd set pointsPerUnit to 50
func drawAxes(in rect: CGRect, origin: CGPoint, pointsPerUnit: CGFloat)
{
UIGraphicsGetCurrentContext()?.saveGState()
color.set()
let path = UIBezierPath()
path.move(to: CGPoint(x: rect.minX, y: origin.y).aligned(usingScaleFactor: contentScaleFactor)!)
path.addLine(to: CGPoint(x: rect.maxX, y: origin.y).aligned(usingScaleFactor: contentScaleFactor)!)
path.move(to: CGPoint(x: origin.x, y: rect.minY).aligned(usingScaleFactor: contentScaleFactor)!)
path.addLine(to: CGPoint(x: origin.x, y: rect.maxY).aligned(usingScaleFactor: contentScaleFactor)!)
path.stroke()
drawHashmarks(in: rect, origin: origin, pointsPerUnit: abs(pointsPerUnit))
UIGraphicsGetCurrentContext()?.restoreGState()
}
// the rest of this class is private
private struct Constants {
static let hashmarkSize: CGFloat = 6
}
private let formatter = NumberFormatter() // formatter for the hashmark labels
private func drawHashmarks(in rect: CGRect, origin: CGPoint, pointsPerUnit: CGFloat)
{
if ((origin.x >= rect.minX) && (origin.x <= rect.maxX)) || ((origin.y >= rect.minY) && (origin.y <= rect.maxY))
{
// figure out how many units each hashmark must represent
// to respect both pointsPerUnit and minimumPointsPerHashmark
var unitsPerHashmark = minimumPointsPerHashmark / pointsPerUnit
if unitsPerHashmark < 1 {
unitsPerHashmark = pow(10, ceil(log10(unitsPerHashmark)))
} else {
unitsPerHashmark = floor(unitsPerHashmark)
}
let pointsPerHashmark = pointsPerUnit * unitsPerHashmark
// figure out which is the closest set of hashmarks (radiating out from the origin) that are in rect
var startingHashmarkRadius: CGFloat = 1
if !rect.contains(origin) {
let leftx = max(origin.x - rect.maxX, 0)
let rightx = max(rect.minX - origin.x, 0)
let downy = max(origin.y - rect.minY, 0)
let upy = max(rect.maxY - origin.y, 0)
startingHashmarkRadius = min(min(leftx, rightx), min(downy, upy)) / pointsPerHashmark + 1
}
// pick a reasonable number of fraction digits
formatter.maximumFractionDigits = Int(-log10(Double(unitsPerHashmark)))
formatter.minimumIntegerDigits = 1
// now create a bounding box inside whose edges those four hashmarks lie
let bboxSize = pointsPerHashmark * startingHashmarkRadius * 2
var bbox = CGRect(center: origin, size: CGSize(width: bboxSize, height: bboxSize))
// radiate the bbox out until the hashmarks are further out than the rect
while !bbox.contains(rect)
{
let label = formatter.string(from: (origin.x-bbox.minX)/pointsPerUnit)!
if let leftHashmarkPoint = CGPoint(x: bbox.minX, y: origin.y).aligned(inside: rect, usingScaleFactor: contentScaleFactor) {
drawHashmark(at: leftHashmarkPoint, label: .top("-\(label)"))
}
if let rightHashmarkPoint = CGPoint(x: bbox.maxX, y: origin.y).aligned(inside: rect, usingScaleFactor: contentScaleFactor) {
drawHashmark(at: rightHashmarkPoint, label: .top(label))
}
if let topHashmarkPoint = CGPoint(x: origin.x, y: bbox.minY).aligned(inside: rect, usingScaleFactor: contentScaleFactor) {
drawHashmark(at: topHashmarkPoint, label: .left(label))
}
if let bottomHashmarkPoint = CGPoint(x: origin.x, y: bbox.maxY).aligned(inside: rect, usingScaleFactor: contentScaleFactor) {
drawHashmark(at: bottomHashmarkPoint, label: .left("-\(label)"))
}
bbox = bbox.insetBy(dx: -pointsPerHashmark, dy: -pointsPerHashmark)
}
}
}
private func drawHashmark(at location: CGPoint, label: AnchoredText)
{
var dx: CGFloat = 0, dy: CGFloat = 0
switch label {
case .left: dx = Constants.hashmarkSize / 2
case .right: dx = Constants.hashmarkSize / 2
case .top: dy = Constants.hashmarkSize / 2
case .bottom: dy = Constants.hashmarkSize / 2
}
let path = UIBezierPath()
path.move(to: CGPoint(x: location.x-dx, y: location.y-dy))
path.addLine(to: CGPoint(x: location.x+dx, y: location.y+dy))
path.stroke()
label.draw(at: location, usingColor: color)
}
private enum AnchoredText
{
case left(String)
case right(String)
case top(String)
case bottom(String)
static let verticalOffset: CGFloat = 3
static let horizontalOffset: CGFloat = 6
func draw(at location: CGPoint, usingColor color: UIColor) {
let attributes = [
NSFontAttributeName : UIFont.preferredFont(forTextStyle: .footnote),
NSForegroundColorAttributeName : color
]
var textRect = CGRect(center: location, size: text.size(attributes: attributes))
switch self {
case .top: textRect.origin.y += textRect.size.height / 2 + AnchoredText.verticalOffset
case .left: textRect.origin.x += textRect.size.width / 2 + AnchoredText.horizontalOffset
case .bottom: textRect.origin.y -= textRect.size.height / 2 + AnchoredText.verticalOffset
case .right: textRect.origin.x -= textRect.size.width / 2 + AnchoredText.horizontalOffset
}
text.draw(in: textRect, withAttributes: attributes)
}
var text: String {
switch self {
case .left(let text): return text
case .right(let text): return text
case .top(let text): return text
case .bottom(let text): return text
}
}
}
}
private extension CGPoint
{
func aligned(inside bounds: CGRect? = nil, usingScaleFactor scaleFactor: CGFloat = 1.0) -> CGPoint?
{
func align(_ coordinate: CGFloat) -> CGFloat {
return round(coordinate * scaleFactor) / scaleFactor
}
let point = CGPoint(x: align(x), y: align(y))
if let permissibleBounds = bounds, !permissibleBounds.contains(point) {
return nil
}
return point
}
}
private extension NumberFormatter
{
func string(from point: CGFloat) -> String? {
return string(from: NSNumber(value: Double(point)))
}
}
private extension CGRect
{
init(center: CGPoint, size: CGSize) {
self.init(x: center.x-size.width/2, y: center.y-size.height/2, width: size.width, height: size.height)
}
}
来处理更改事件。我已将输入放在一系列变量中：
.on("change")每个变量都有一个jQuery选择器，如下所示：
$(document).on("change keyup", [
input1,
input2,
input3
], function() {
// doing stuff
});
每个输入都有一个数据属性，我希望在输入更改时从var input1 = $("input[name=input1]");
var input2 = $("input[name=input2]");
var input3 = $("input[name=input3]");
上下文获取该属性。例如，如果input1已被更改，我想通过以下方式获取其数据属性：
this但我担心this.data("someAttribute")
无法使用this功能的选择器，但使用最初的.on()选择器，而我实际上是尝试从$(document)获取数据属性，而不是我所需要的已更改的输入。
注意：根据我尝试做的事情，选择像document这样的多个输入并不适用于我的情况。
答案 0 :(得分：1)
不是将需要绑定到数组中的输入分组并将数组传递给.on()方法（无论如何也不允许），您应该给出问题的input个元素常见的CSS类然后像这样编写你的事件绑定：
$(document).on("change keyup", ".theClass", function() {
// doing stuff
});
然后，在事件处理程序中，您需要将this传递给JQuery函数，如下所示：$(this).data()因为.data()是一个JQuery方法并赢得了＃{1}}。在this单独引用的原生DOM元素上可用。
以下是一个例子：
$(document).on("change keyup", ".input", function() {
console.log($(this).data("test"));
});<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type='text' name='input1' class="input" data-test='one'>
<input type='text' name='input2' class="input" data-test='two'>
<input type='text' name='input3' class="input" data-test='three'>
答案 1 :(得分：0)
为所有输入提供CSS类
$('.change').on('change keyup', function() {
console.log($(this).val());
})<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" class="change">
<input type="text" class="change">
<input type="text" class="change">